Recycling waste cellulosic material with sodium sulphide digestion

ABSTRACT

An installation for recycling waste cellulosic material to produce a cellulose fiber pulp and recover energy and chemical values comprises: a re-pulper (16) means for waste cellulosic material, dewatering means (22) for dewatering an aqueous pulp, a digester (26) for delignifying waste pulp to a delignified pulp having a kappa number lower than that of the waste pulp, a brownstock washer (30), a first line means (36,38,42) for feeding re-pulped paperboard from said re-pulper means to said dewatering means, a second line means (70) for feeding dewatered pulp from said dewatering means to said digester, a third line means for feeding cooking liquor to said digester (58,60), a fourth line means (78) for feeding a brownstock from said digester to said brownstock washer, a fifth line means (82) for removing washed pulp from said brownstock washer, a sixth line means (80) for removing brownstock washing liquor from said brownstock washer, furnace means (88) for combusting organic substances in the liquor removed by said sixth line means, and for developing inorganic chemical values, heat energy recovery means (68) for re-covering heat energy developed in said furnace means, and reactor means for generating cooking liquor from said inorganic values (94). &lt;IMAGE&gt;



